Artificial limb



I. TOUSON ARTIFICIAL LIMB June 3; 1952 4 Sheets-Sheet 1 Filed Oct. 28,1949 INVENTOR Isaac Tousow.

A TTORNEY June 3, 1952 v l. TOUSON ,5

I ARTIFICIAL LIME Filed Oct. 28, 1949 4 Sheets-Sheet 2 INVENTOR. IsaacTousoro.

ATTORNEY I. TOUSON ARTIFICIAL LIMB June 3, 1952 4 Sheets-Sheet 3 Filed001:. 28, 1949 2 ms w T 5 ATTORNFY June 3, 1952 l. TOUSON 2,599,297

' ARTIFICIAL LIMB Filed Oct. 28. 1949 4 Sheets-Sheet 4 Isaac Touson.

A TORNEY Patented June 3, 1952 UNITED STATES PATENT QFFI CEApplicationOctoher.;28,'1949; Serial Nor-124,201 InVAr-gentinaAugust-31; 1949 6' Claims.

The-present.invention relates. to. artificial legs forrusesbmpersons whohave had amputations above the :knee.

It isxaprincipal object of thepresent inven-r tion to. provide aknee-joint which, while it shall enable the amputee to move at will, themere movementlof the stump or the body, the vtwo parts of the leg from astraight position to different angular. positions, shall always afiord apositive lockingof the parts which shall impede further bending orcollapse of the joint in response. to .the weight of the body, therebypreventing falls or -,loss of equilibrium.

A further object is to provide av knee-joint which;shall enableothe legto bezbent. to a given anglee-atv-willandv to. be then subjectedto theload ofqtthe, wearer persons without danger that it continue to. bend,,and forthe return. to the straight; position, shall requireonly tobelifted by a;simple.movementflofthe stumpor .by inclination .Of'thebodytogether with the transfer to the-other leg oftheweight ofjthe body.

A further object is to provide a knee-joint which shall, enable thewearerreadily and reliamy, to :.perform the movements, ,of walking andevenrgoing upland down stairs, sittingdown and other' similar actionswithin the range of the natural member.

Anothercfthe' objects of the invention is to provide'an artificial legcomprising a knee joint having structural features including cooperatingconvex and concavesubstantially parabolic surfaces-which enable the shinportion to perform onsimulate the movements of the human leg inarhighlynatura'lmanner.

Another object is' to provide a leg" including a knee joint-comprising amain connection of the shin-portion-with thethigh portion which willpermit" coordinated relative movements at the knee; and "auxiliaryconnection means for connecting the thigh portion and the shin portionin suchamanner that the shin portion is automatically' andresilientlyurged' to straight leg position :w ith'reference to thethigh'portion.

With the: above and other objects in ,view. which" will more readilyappear as the nature of theinventi'on is better underst'oodJthe samecon,- sists in "the-features shown in the accompanying" drawings inwhich:

Figure 11, is a side. elevations.offtheimproized artificial :jleg with,the lower. unit shownmpartly inf secti'on;

F ure; 2 is a rear elevation, i partly in, section, ofth' le iofi Figure1';

Fi'gureo3lji's anhorizontal, sectional View. takenon'.;the".line-13.3;oi- Figure 2;

F u e 4. is a? horizontal "sectional new: taken on the. line 4-4 ofFigure 2;,

Figure 5 isa horizontal sectional view taken on the line 5-5 of Figure2;

Figure 6 is a detail elevationof the automatic actuating deviceiorimpelling the twounits composing the leg into the-normal uprightposition;

Figure 7 is aside elevation on a reduced scale of -the:two. unitscomposing the leg, in both. a vertical and an angular position,respectively;

Figure 8 is a perspective view. of the lining which guides the movementof the transverse pin joining the two unitsin the region of'rotularconnection;

Figure 9 isa' fragmentary detail; showinguthe connection between. thetransverse pin. and the flexible, lining;v

Figure 10. is a detail sectional view. alonggline. llll0 of Figure 9;.

Figurel'l is a fragmentary side elevation partly inisection ofthe-structure shown in Figureilo.

Similar-numerals and reference characteristicnote the same orcorresponding parts intheiseveral views.

In accordance with'the accompanyingdrawings,- the improved artificialleg comprises-. ian upper or thigh unit a and a lower foreleg sec tionor; peroneotibial unit I), The latterissecured by its lower end to. thecomplementary unit 0, consistingiof the. foot.

The upper unit a has,- at its lower end, a substantially parabolic wallsurface I constituting the area of sliding. contact with the concaveparabolic wall surface Ziatthe upperLor-socketend of the lower unit 6.Interposed between these surfaces. are the yielding frictionalf con.-tact members which will hereinafter be described more in detail.

The unitsa and b, are articulated byaknee bolt. arrangement hereafterdescribed operating in conjunction with, automatic. stabilizer or con:-trolmeans 642 and 23 and'24, and 'a'guiding' transverse pin and slotarrangement. First; it willibe seen that. the upper unit a is providedwith av transverse pin. 3 connected with the lat eral ears 4 of thelower unit b, said pin being movable within slot 5 provided intheilbwerv part or kneeportion of the upper unit a. 7

As. previouslyindicated, the improvements herein consist. in anarrangement for-automati cally-urzing'ithe twoounits a'and bi into.th'ejinior malwupri ht position corres onding to the verv-v ticalposition. of vthe. user on the ground when standingstill, asshown. inFigure 1., SaidLare rangement comprises anielongatedahollow memi:

her 6 anchored to the lower unit I) by pivot I fastened to a forkedbracket 8 (Figs. 1 and 5) with interposition of a ball bearing race 5(Fig. 6) occupying a cavity provided in the widened end IU of elongatedmember E. Bracket 8 has its web 39 secured to the inner rear part ofunit b by fastenings 33 not far from foot c while its arms 34 supportthe pivot l.

The elongated member 6 has an axial bore or cavity I l which receivesthe lower part of a solid control rod 12, a helicoidal spring i3(Fig. 1) being interposed between that end of the rod which enterscavity H and the bottom of said cavity. The upper end of rod I2 extendsinto the thigh unit a through a slot Hi (Fig. 2) and terminates in aneye l5. This eye receives a ball bearing race I8 whose inner shell issupported on a stud H (Fig. 3) received within the bushings l9 havingintegral flanges 19a for firmly abutting against the sides of the eye 5.ends of the bushings are in the nature of bolts 20 which are secured inopposite sides of the thigh unit atatably mounted on the ends of atransverse shaft 2| of rod [2 near the concave parabolic surface 2 ofunit b, said rod 52 carries two rollers 23 guided in rails 24 secured tothe inner face of surface 2, the said rollers, in cooperation with therails, constituting means for compelling the movement of rod [2 forwardor backward, without lateral displacements.

Transverse pin 3 is guided in a lining 25 of flexible material providedin slot 5 of the upper unit a. The length of the lining corresponds tothat of slot 5 and silences the sliding movement of the transverse pinin an eificient manner.

The transverse pin has at its opposite end a stud 2'6 onto which a nutis screwed, the said stud being engaged by a roller bearing assembly 27mounted in ear d of unit I), as shown in Figure 10. Retention nuts 28secure the said studs on either side of the upper unit a. Theinter-position of roller bearing imparts greater sensitivity to therotary movement of the pins, thus facilitating the angular motions ofboth units a and b in accordance with the motions of the users The lowerwidened end it of the elongated member 6 ends in a radial cam portion2:? against the free end of which bears the end of a laminar spring 30(Figs. 1 and '7). Said spring and helicoidal spring l3 cooperatingtherewith constitute the elastic means for urging the two units a and binto the normal position shown in Figure 1 by means of members 6 and 12,upon which said springs act in the directions indicated by the arrows Ffor spring 13, and F for spring Bil, respectively.

As an alternative for the cam 25 and spring 30, or in supplement theretoas shown in Figure l, the lower section 6 of the telescopically engagedparts 6 and 12 may be tensioned in the direction of the arrows F by aresilient loop an anchored about the part 6 and connected with a screwywhich in turn is engaged by the intern ally threaded portion a of asleeve 2 of a control nut 2, so that by operating the nut, the screw 3/will be moved in the direction of its axis to impose more or lesstension on the loop r.

To the concave parabolic upper face 2 of the lower unit b there issecured a flexible laminar member 3|. In frictional contact therewith isa lining 32 of shorter length provided in the rear part of the convexparabolic end 2 of the upper unit 11. These two laminar elastic members3| The reduced and 32 form surfaces of yielding, constant contact in anyof the positions into which the units a and b may be urged under theload of the body indicated in Figure 11 by the arrows F".

Bearing all of these hereinabove described structural features in mind,the operation of the artificial leg according to the present inventionwill be readily understood.

Starting from the straight position of the leg when worn by an amputee,the resilient inserts 32 will be pressed down against the concavesurface 2 of 3! and concave closure member 36, and, since said inserts32 yield a little under compression, will thus cause a load to beimposed substantiallyv axially on connection member 5. thereby pushingrod i2 slightly into tubular member H and compressing spring is anddepressing the rollers 23. When it is desired to bend the knee as inmounting a stair, the wearers weight is first transferred from theartificial leg to the other so that the load is removed from theconnecting member 15 and spring 13 expands to raise the rod member l2thereby slightly lif ing the rear part of the thigh portion a so as toprepare same for easier swinging, and also bringing the rollers 23 intoengagement with the exposed surfaces 32 of rails 24 to prevent therearward part of the end of the thigh portion a from being lifted out ofthe aforesaid troughlike cavity.

As the artificial knee is bent as hereinbefore described, the resilientinserts 32 move forward over concave surface 2 and the pin I? will alsomove forward and also downward towards said surface 2 thereby causingconnecting member 8 to s ving around lower pin l and the rod member 12to be pushed into the tubular member H thereby compressing spring l3 andcausing roll-v ers 23 to be retracted from the rails 24, and at the sametime the cam projection 29 will depress the leaf spring 38, and the loopat will be tensioned as hereinabove described.

The compressed and depressed springs and tensioned loop will nothowever, be effective to prevent bending of the knee or to assist inreturning the leg to the straight position so long as there is a loadupon the leg as hereinabove made clear. As soon as the load is relieved,as by the commencement of a straightening movement, the leaf spring 38and the loop a: will apply forces to the connection member 6 to restoresame to its normal position and the coil spring l3 will exert an upwardthrust on rod l2 tending to lift the rear part of the end of the thighportion a,

so as to keep the resilient inserts 32 floating over the surface 2 andthus prevent accidental jamming, while the rollers 23 will gradually bebrought closer to the rails 24 which they engage towards the end of thereturn stroke.

I claim:

1. An artificial limb, comprising, a thigh unit including a knee-portionhaving curved slots in its opposite side walls and a vertical slot inits rear wall, a foreleg unit including a knee-portion receiving socket,mating arcuate wall portions at the knee-portion and socket portions ofsaid units, a transverse pin carried by the foreleg section and guidedin said slots, a knee-bolt transversely mounted in the rear of thekneeportion of the thigh unit, and automatic means for. urging thethighand foreleg units into vertical alignment, said means comprisingsolid and hollow members telescopically connected at their inner ends,means for connecting theouter end of said solid member to the knee-bolt,and pivot and bracket means for connecting the outer end of the hollowmember to the inner wall of the foreleg unit, parallel track members onthe wall of the socket portion of the forele member, guide rollers onthe said solid member for engaging said track members, and means forexerting a yielding lateral force on said telescopically related solidand hollow members.

2. An artificial limb according to claim 1, wherein, the curved slots inthe knee-portion of the thigh unit are provided with resilient linings.

3. An artificial limb according to claim 1, wherein, the means forexerting a yielding lateral force on said telescopically related solidand hollow members comprises a cam offset from the end of the hollowmember and a leaf spring carried by the bracket and engaging said cam.

4. An artificial limb, comprising, a thigh unit including a knee portionhaving arcuate slots in its opposite sides and also having an arcuatebearing wall, a foreleg section having an arcuate bearing wall includingspaced strips having guides on their lower faces, a transverse pincarried by the foreleg section and guided in said arcuate slots, acontrol rod pivoted at one end in the thigh unit and extending into theforeleg unit, rollers on the control rod engaging in said guides, andyielding means cooperating with said con trol rod to urge it in adirection to force the thigh and foreleg units in vertical alignment. I

5. An artificial limb, comprising, a thigh unit and a foreleg unithaving arcuate mating knee portions, a knee bolt in the thigh unit, andcontrol means tending to keep the units in vertical alignment andincluding a pair of telescopic members, one of saidmembers beingpivotally supported at its upper end by the knee bolt and extending intothe foreleg unit and having a resilient connection therewith, guidemeans on the arcuate knee portion of the foreleg unit. rollers carriedby said last mentioned member and bearing in said guide means, and theother of said members being pivotally connected to a bracket in theforeleg unit.

6. An artificial limb, comprising, a thigh unit and a foreleg unithaving arcuate mating knee portions, a knee bolt in the thigh unit,control means carried 'by said bolt and extending into the foreleg unitand having a resilient connection therewith comprising a resilient loopanchored to the coltrol means, tensioning means for said resilientconnection and comprising a screw connected with the loop, and arotatable nut held in the foreleg unit against axial movement andengaging the screw.

ISAAC TOUSON.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 766,686 Gault Aug. 2, 19042,466,134 Touson Apr. 5, 1949 FOREIGN PATENTS Number Country Date326,232 Germany Sept. 25, 1920

